docs: def _extract_docs_description(self):
          """Extract main description from docstring"""
          # FIXME: the indentation of descriptions is lost
          data = '\n'.join([d.rstrip().replace(self.docs['out']['spaces'], '', 1) for d in self.docs['in']['raw'].splitlines()])
          if self.dst.style['in'] == 'groups':
              idx = self.dst.get_group_index(data)
          elif self.dst.style['in'] == 'google':
              lines = data.splitlines()
              line_num = self.dst.googledoc.get_next_section_start_line(lines)
              if line_num == -1:
                  idx = -1
              else:
                  idx = len('\n'.join(lines[:line_num]))
          elif self.dst.style['in'] == 'numpydoc':
              lines = data.splitlines()
              line_num = self.dst.numpydoc.get_next_section_start_line(lines)
              if line_num == -1:
                  idx = -1
              else:
                  idx = len('\n'.join(lines[:line_num]))
          elif self.dst.style['in'] == 'unknown':
              idx = -1
          else:
              idx = self.dst.get_elem_index(data)
          if idx == 0:
              self.docs['in']['desc'] = ''
          elif idx == -1:
              self.docs['in']['desc'] = data
          else:
              self.docs['in']['desc'] = data[:idx]